statistics and sample surveys also indicate a decline in the birth rate.* As among the countries with more reliable statistics, a majority apparently have experienced reduction of the birth rate in the 1960's. This leaves the giants of the less developed world unaccounted for—mainland China, India, Pakistan, Indonesia, Brazil, and Nigeria. In these countries available information gives no solid basis for saying with assurance that these countries had a reduction of natality in the 1960's; nor, indeed, is there any better evidence that they did notJ In order to reach European levels of fertility the birth rate must fall to 20 or below. A rough (though somewhat narrow) measure of countries "in transition" are those with birth rates in the range of 25 to 35. In 1960 there were few such countries, and of these even fewer could be regarded as undergoing initial transition.? All but Cuba and Israel have since dropped below this category, but a growing list of new countries was approaching, entering, and passing through this range. (See Table 1.) In quite recent years there have been important breakthroughs in the cultural and climatic barriers to spread of lower birth rates. The most important of these is the diffusion of lower birth rates in east Asia, first established in Japan and now spreading to neighboring countries. Taiwan and Koreas are experiencing rapid declines in the birth rate, a trend that antedates the successful family planning programs in these countries, though the latter have surely accelerated adoption of birth control. The birth rates of Chinese populations in Hong Kong, Singapore, and Malaysia are also falling rapidly. Most important is, of course, mainland China. What little evidence is available from very *These countries include South Korea, Iran, Turkey, Lebanon (in number of births), the United Arab Republic, Cuba, Colombia, Ecuador, and miscellaneous smaller areas. tIndirect evidence suggests the possibility of slight fertility reduction in India (as indicated by the enlarged family planning program and, especially, survey results showing rising use of contraception, especially in urban populations); in Pakistan as a result of the wide acceptance of contraception in the family planning program before the change of government in 1968; in China in connection with the campaign to raise age at marriage and to provide birth control services; and, in tropical Latin America as result of the incidence of induced abortion. In all countries there has been an increase of ur-banism, education, and other variables that historically have been associated with reduction of birth rates. Counteracting these influences is the possibility that in some areas birth rates may have risen (as they did earlier in Latin America) as the result of improved health conditions. $The countries with birth rates between 25 and 35 were Canada and New Zealand, then still experiencing the postwar "baby boom"; three countries related to Europe: Iceland, Israel, and Malta; and three Caribbean countries: Barbados, Cuba, and Puerto Rico. §In South Korea official vital statistics are defective, but annual enumerations provide tabulations which show declining proportions of young children, as does the census of 1966. These are confirmed by repeated sample surveys conducted for evaluation of the Korean family planning program.